The emoji.json file released with version 6.0.0 does not contain any entries for Unicode 13 emojis. It also contains some obsolete short names, such as bride_with_veil, which is now called person_with_veil, so it cannot be converted using shortnameToImage().
The emoji.json in the master branch seems to be correct, but is different from the version released with 6.0.0.
The emoji.json file released with version 6.0.0 does not contain any entries for Unicode 13 emojis. It also contains some obsolete short names, such as bride_with_veil, which is now called person_with_veil, so it cannot be converted using shortnameToImage().
The emoji.json in the master branch seems to be correct, but is different from the version released with 6.0.0.